Abstract: A network relay device includes a packet buffer for temporarily storing a received packet, and a packet buffer control section for changing an effective buffer number depending on the received amount of packet. When a traffic amount is small, the packet buffer control section reduces the power consumption by stopping the feeding of power or the supply of clock to a part of the packet buffers. The network relay device further includes plural table memories storing a table for deciding the transfer destination of packet, and a table memory control section for changing an effective table number according to a required number of table entries. When the required table entry number is small, the table memory control section reduces the power consumption by stopping the feeding of power or the supply of clock to a part of the table memories.

Abstract: It is provided a communication apparatus for transferring frames, comprising: a controller for controlling operation of the communication apparatus; an interface for inputting/outputting the frames; and a plurality of frame processing parts for processing the input frames. The plurality of frame processing parts each includes: a plurality of storage areas for recording statistics of the frames to be processed; an identifier assigning part for determining, for each of the input frames, one storage area in which the statistics are to be recorded out of the plurality of storage areas, and assigning identification for identifying the determined one storage area to the each of the input frames; and a statistical processing part for updating the statistics that are recorded in the one storage area identified by the identification, by using a result of statistical processing of the frame.

Abstract: An authentication switch monitors a failure of an external server, and redirect information to a Web server that holds authentication information registration screen data is provided to a terminal using a monitoring result. A life-and-death monitoring control unit for monitoring life and death of an external Web server is disposed within an authentication switch to monitor the life and death of the external Web server. An authentication processing unit within the authentication switch switches the redirect information on the basis of a life-and-death monitoring table of the external Web server provided in the life-and-death monitoring control unit in response to an authentication request from the terminal, and enables web authentication even when the external Web server is in failure.

Abstract: The network relay device is provided. The network relay device includes: a plurality of ports, each being configured to be connectable with one physical line; a virtual line controller configured to treat a plurality of physical lines, which are respectively connected with the plurality of ports, to constitute a virtual line; and a status check frame controller configured to send via the virtual line a status check frame for use in checking status of a network, which the network relay device is connected with via the virtual line, wherein the status check frame controller changes a frame-sending port to be used to send a next status check frame, in order to avoid continuously using an identical port as both a frame-sending port to send the status check frame and a frame-receiving port to receive the status check frame from another network relay device.

Abstract: A first network device includes: a forwarding controller configured to forward received data; and a fault detector configured to detect occurrence of a failure in a remote second relay node. The forwarding controller includes: a forwarding unit configured to forward the received data; and a modifier configured to modify the received data for detection of the occurrence of a failure in the second relay node. The modifier includes (i) a flag option marker configured to attach a flag to data; (ii) a sequence adding unit configured to add a protocol specific number to a sequence number; and (iii) a sequence subtracting unit configured to subtract the protocol specific number from an acknowledgement number. The fault detector detects the occurrence of a failure in the remote second relay node, based on at least one of the flag and the acknowledgement number.

Abstract: A management apparatus includes user group information for managing the terminals by grouping terminals into groups each corresponding to service use conditions of terminals belonging to the group, and service information for associating each of the services provided by the service providing resources with paths for passing data when a terminal uses the service and a failure group which is affected by a failure when the failure occurs in one of the paths. When a failure occurs in one of the paths in the network, the management apparatus refers to the service information to identify a service for which the paths in the service information include the failed path as a failed service, identifies a failure group associated with the identified failed service, refers to the user group information to identify terminals belonging to the identified failure group as failure terminals, and reports the identified failure terminals.

Abstract: A data transfer apparatus includes a first memory, a second memory, a search unit, and a data transmitting/receiving unit. The first memory holds information that associates a search key with an address. The second memory holds information that associates the address with verification information which is generated by a predetermined generation method based on at least a portion of the search key. The search unit generates the search key based on the received data, obtains, from the first memory, the address that is associated with the generated search key, obtains, from the second memory, the verification information that is associated with the obtained address, and verifies the verification information that is generated by the predetermined generation method based on at least a portion of the generated search key with the verification information obtained from the second memory. The data transmitting/receiving unit executes processing based on a result of the verification.

Abstract: A relay device of relaying a communication packet is disclosed, which comprises: an input module configured to receive the communication packet as an input; a buffer configured to have a plurality of queues and temporarily accumulated the received communication packet; a sorter configured to sort the received communication packet to one of the plurality of queues, depending on a specific value obtained by a predetermined function that gives an aggregate output from an input which is transfer information regarding transfer of the communication packet; and a band controller configured to control a bandwidth for each of the plurality of queues and output communication packets accumulated in the plurality of queues for transmission of the communication packets. This ensures the quality of service, while saving the capacity of the buffer used for the queues.

Abstract: A network device 200 for relaying packets includes a network interface 220, a forwarding engine 240, a state change controller 274, a device state controller 276 and a device information table 278. The state change controller 274 and the device state controller 276 cooperatively determine whether a packet receiver port that has received a sleep notification packet among a plurality of ports included in the network interface 220 has setting of link aggregation. When link aggregation is set for the packet receiver port, the state change controller 274 and the device state controller 276 keep the packet receiver port in a power ON state, while all other ports, which belong to an identical link aggregation group are to a power OFF state.

Abstract: The packet relay apparatus is provided. The packet relay apparatus includes a receiver that receives a packet; and a determiner that determines to drop the received packet without storing the received packet into a queue among the multi-stage queue. The determiner determines to drop the received packet at a latter stage, based on former-stage queue information representing a state of a queue at any former stage which the received packet belongs to and latter-stage queue information representing a state of a queue at the latter stage which the received packet belongs to.

Abstract: A network system comprises a first communication device having a first address connected, using a network, to a second communication device having a second address. The first communication device includes a monitor frame transmitter configured to generate a monitor frame including the second address as a destination address and the first address as a source address, and to output the generated monitor frame to the network; and a monitoring-response frame monitor configured to monitor reception of a monitoring-response frame sent back from the second communication device. The second communication device includes: a monitoring-response frame transmitter configured to, in response to reception of the monitor frame, generate the monitoring-response frame by exchanging the destination address in the received monitor frame for a source address and the source address in the received monitor frame for a destination address, and output the generated monitoring-response frame to the network.

Abstract: In a ring network including an old master node 100, a new master node 110 is used as a replacement for the old master node 110. During replacement operation, when detecting that two ring ports of the new master node 110 are set in link-up state, the new master node 110 gives a transit node 200 an instruction to forward a health check frame H102 sent from a ring port 102 of the old master node 100 by a forwarding route going through the new master node 110. The new master node 110 can monitor the status of the ring network by receiving the health check frame H102. This configuration enables continuous monitoring for a failure occurring in the ring network during replacement of the master node.

Abstract: The network relay apparatus includes: a plurality of distributed processing units configured to receive and send a packet from and to an external device; an integrated processing unit connected with the plurality of distributed processing units; and a mode selector configured to change over a processing mode of the network relay apparatus between a distributed processing mode and an integrated processing mode, based on at least either one of a load applied to the network relay apparatus and a packet type determined according to header information of the received packet.

Abstract: Provided is a network management system for managing a plurality of packet relay devices, the network management system comprising: the plurality of packet relay devices constituting networks; and a display device for displaying configurations of the networks, in a case where it is determined that a virtual packet relay device identifier of the virtual packet relay device that is assigned a second-network identifier associated with the extracted second-network identifier is registered in a first-network configuration table, a first-work identifying module is configured to associate a first-network identifier that is associated with the virtual packet relay device identifier with the obtained configuration information, and register the association between the first-network identifier and the obtained configuration information in the first-network configuration table.

Abstract: In a virtual network apparatus, even when a fault occurs on a private line connecting plural physical network apparatuses to communicate a control signal, the redundancy is maintained, and the lower forwarding capability is prevented. In this network system, a control signal for virtualization to be transmitted and received between plural physical network apparatuses is relayed via a unit spanning LA connecting each physical network apparatus and an adjacent network apparatus in the adjacent network apparatus. Thereby, even when a fault occurs in the private line, it is possible to continue to communicate the control signal between the physical network apparatuses and continuously operate the virtual network apparatus.

Abstract: A first network switching device communicates to and from a second network switching device different in at least one of a device configuration and a device performance. The network switching device has at least one of plurality of network interface units and packet forwarding unit which is a power state control subject. A power state control unit of the first network switching device transmits, in order to change the power state of the second network switching device, a forwarding performance notification including the forwarding performance of a power state control subject after the change to the second network switching device.

Abstract: A packet relay apparatus keeps only packets specified as authentication target packets of MAC address authentication, to reduce the number of packets to be transferred from H/W to a CPU. In addition to a source MAC address, the authentication target packet of MAC address authentication is specified by an Ethernet type, a destination IP address, a protocol, a source port number and a destination port number of TCP/UDP, and the like. In this way, the packet relay apparatus excludes a terminal not transmitting authentication target packets of MAC address authentication, from the MAC address authentication target, while allowing selection from other authentication methods such as Web authentication and IEEE802.1X authentication.

Abstract: When a delay between a packet relay device and a receiving terminal increases, congestion notifications are delayed, and communication quality declines. When a flow is assessed to be in a congestion state, a packet delay device overwrites, within a packet header of an acknowledgement packet for the flow which is received thereafter from a receiving terminal, a field which denotes a network congestion state with a value which denotes that a congestion state is in effect, and transmits same as an acknowledgement packet. It is thus possible to issue a congestion notification over a path from the packet relay device to the receiving terminal, eliminating a congestion notification path from the packet relay device to the receiving terminal and from the receiving terminal to the packet relay device, facilitating avoiding a decline in communication quality even if the delay between the packet relay device and the receiving terminal increases.

Abstract: A system having a plurality of network devices, each including: an interface module including a plurality of physical ports to transmit and receive packets; a computing module configured to execute a computing process with a computational expression using seed information, the seed information including at least one of destination information and source information associated with a received packet; a destination search module configured to, based on the result of the computation, select a physical port for transmission of the received packet from a plurality of candidate ports among the plurality of physical ports; and a modifying module configured to modify the computational expression, wherein the plurality of network devices include preceding-stage and subsequent-stage network devices, the subsequent-stage network device being directly coupled to the preceding-stage network device with physical wiring, and wherein the subsequent-stage and preceding-stage network devices are configured to use different exp

Abstract: Network switching arrangements including: setting an operation mode of a target switching block to a operation mode that is different from an operation mode of a first switching block while the first switching block is handling a switching process, the target switching block being one switching block selected from second switching blocks; performing a switchover process including starting the switching process using the target switching block instead of the first switching block, after completion of setting the operation mode of the target switching block; and copying the switching information held by the first switching block to the target switching block, prior to starting the switching process using the target switching block, after completion of setting the operation mode of the target switching block.